<!DOCTYPE html>
<html>

<head>
    <meta charset="utf-8">
    <title>菜鸟教程(runoob.com)</title>
</head>

<body>

    <script>
        function person(firstname, lastname, age, eyecolor) {
            this.firstname = firstname;
            this.lastname = lastname;
            this.age = age;
            this.eyecolor = eyecolor;
        }
        myFather = new person("John", "Doe", 50, "blue");
        document.write(myFather.firstname + " is " + myFather.age + " years old.");
    </script>

</body>

</html>